Corrigendum: Association of airway obstruction with first-pass success and intubation-related adverse events in the emergency department: multicenter prospective observational studies

[This corrects the article DOI: 10.3389/fmed.2023.1199750.].

First-Pass Success of Video Laryngoscope Compared With Direct Laryngoscope in Intubations Performed by Residents in the Emergency Department

BACKGROUND

The video laryngoscope (VL) has been widely used for intubation in the emergency department (ED). However, their effectiveness remains controversial, particularly among airway management performed by residents in the ED.

METHODS

We aimed to examine whether the use of VL, compared to a direct laryngoscope (DL), was associated with higher first-attempt intubation success among intubations performed by residents in the ED. This is a secondary analysis of the data from a prospective, observational, multicentre study of 15 Japanese EDs from April 2012 through March 2020. We included all adult patients who underwent intubation with VL or DL by residents (postgraduate years ≤5) in the ED. The outcome measures were first-pass success and intubation-related adverse events (overall, major, and minor adverse events). To determine the association of VL use with each of the outcomes, we constructed logistic regression models with generalized estimating equations to account for patients clustering within the ED, adjusting for patient demographics, primary indications, intubation difficulty, and intubation methods.

RESULTS

Of 5,261 eligible patients who underwent an initial intubation attempt by residents, 1,858 (35%) patients were attempted with VL. Intubations performed with VL had a non-significantly higher first-pass success rate than those with DL (77% vs. 64%; unadjusted odds ratio (OR)=1.20; 95% CI=0.87-1.65; P=0.27). This association was significant after adjustment for potential confounders (adjusted OR, 1.33; 95% CI, 1.06-1.67; P=0.01). As for adverse events, the use of VL was associated with a lower rate of any (adjusted OR=0.67; 95% CI=0.51-0.86; P=0.002) and minor (adjusted OR=0.69; 95% CI=0.55-0.87; P=0.002) adverse events.

CONCLUSION

The use of VL was associated with a higher first-attempt success rate and a lower rate of any adverse events compared to that with DL among intubations performed by residents in the EDs.

Differences in left and right carotid plaque vulnerability in patients with bilateral carotid plaques: a CARE-II study

BACKGROUND AND PURPOSE

Atherosclerosis is a very complex process influenced by various systemic and local factors. Therefore, in patients with bilateral carotid plaques (BCPs), there may be differences in carotid plaque vulnerability between the sides. We aimed to investigate the differences in BCP characteristics in patients with BCPs using magnetic resonance vessel wall imaging (MR-VWI).

METHODS

Participants with BCPs were selected for subanalysis from a multicentre study of Chinese Atherosclerosis Risk Evaluation II. We measured carotid plaque burden, identified each plaque component and measured their volume or area bilaterally on MR-VWI. Paired comparisons of the burden and components of BCPs were performed.

RESULTS

In all, 540 patients with BCPs were eligible for analysis. Compared with the right carotid artery (CA), larger mean lumen area (p<0.001), larger mean wall area (p=0.025), larger mean total vessel area (p<0.001) and smaller normalised wall index (p=0.006) were found in the left CA. Regarding plaque components, only the prevalence of lipid-rich necrotic core (LRNC) in the left CA was higher (p=0.026). For patients with a vulnerable plaque component coexisting on both sides, only the intraplaque haemorrhage (IPH) volume (p=0.011) was significantly greater in the left CA than in the right CA.

CONCLUSIONS

There were asymmetries in plaque growth and evolution between BCPs. The left carotid plaques were more likely to have larger plaque burden, higher prevalence of LRNC and greater IPH volume, which may contribute to the lateralisation of ischaemic stroke in the cerebral hemispheres.

Association of airway obstruction with first-pass success and intubation-related adverse events in the emergency department: multicenter prospective observational studies

Background

Airway obstruction is a relatively rare but critical condition that requires urgent intervention in the emergency department (ED). The present study aimed to investigate the association of airway obstruction with first-pass success and intubation-related adverse events in the ED.

Methods

We analyzed data from two prospective multicenter observational studies of ED airway management. We included adults (aged ≥18 years) who underwent tracheal intubation for non-trauma indications from 2012 through 2021 (113-month period). Outcome measures were first-pass success and intubation-related adverse events. We constructed a multivariable logistic regression model adjusting for age, sex, modified LEMON score (without airway obstruction), intubation methods, intubation devices, bougie use, intubator's specialty, and ED visit year with accounting for patients clustering within the ED.

Results

Of 7,349 eligible patients, 272 (4%) underwent tracheal intubation for airway obstruction. Overall, 74% of patients had first-pass success and 16% had intubation-related adverse events. The airway obstruction group had a lower first-pass success rate (63% vs. 74%; unadjusted odds ratio [OR], 0.63; 95% CI, 0.49-0.80), compared to the non-airway obstruction group. This association remained significant in the multivariable analysis (adjusted OR 0.60, 95%CI 0.46-0.80). The airway obstruction group also had a significantly higher risk of adverse events (28% vs. 16%; unadjusted OR, 1.93; 95% CI, 1.48-2.56, adjusted OR, 1.70; 95% CI, 1.27-2.29). In the sensitivity analysis using multiple imputation, the results remained consistent with the main results: the airway obstruction group had a significantly lower first-pass success rate (adjusted OR, 0.60; 95% CI, 0.48-0.76).

Conclusion

Based on these multicenter prospective data, airway obstruction was associated with a significantly lower first-pass success rate and a higher intubation-related adverse event rate in the ED.

Atherosclerotic carotid plaque characteristics vary with time from ischemic event: A multicenter, prospective magnetic resonance vessel wall imaging registry study

Recent studies report that the rate of recurrent stroke is highest in the stages immediately following cerebral infarction and decreases over time in patients with atherosclerotic carotid stenosis. The purpose of this study was to identify temporal differences in early stage carotid plaque components from acute cerebrovascular ischemic events using carotid MRI. Carotid plaque images were obtained on 3 T MRI from 128 patients enrolled in MR-CAS. Among the 128 subjects, 53 were symptomatic and 75 asymptomatic. The symptomatic patients were classified into three groups based on interval from onset of symptoms to the date of the carotid MRI (Group <14 days; 15-30 days; and > 30 days). The volume of each plaque component was identified and quantified from MR images. The presence of juxtaluminal loose matrix/inflammation (LM/I) was identified as a possible indicator of inflammation on the luminal side. Plaque components were compared between groups using the Wilcoxon rank-sum or the Chi-square test. Patient characteristics and carotid plaque morphology were similar among all four groups. The median volume of LM/I in Group >30 days was significantly lower than in other groups (0 mm3 vs 12.3 mm3 and 18.1 mm3; p = 0.003). In addition, the prevalence of juxtaluminal LM/I decreased over time (ptrend = 0.002). There were no statistically significant differences in other plaque components between the symptomatic groups. The volume of LM/I was significantly smaller in Group >30 days and prevalence of juxtaluminal LM/I in the atherosclerotic carotid plaque was high in the early stages after events. This suggests that carotid plaques undergo rapid evolution after an acute cerebrovascular ischemic event.

Association of Number of Physician Postgraduate Years With Patient Intubation Outcomes in the Emergency Department

This cohort study examines the association between the number of physician postgraduate years and intubation outcomes among patients undergoing airway management in the emergency department.

Association Between Repeated Tracheal Intubation Attempts and Adverse Events in Children in the Emergency Department

STUDY OBJECTIVES

Studies have shown that multiple intubation attempts are associated with a higher risk of intubation-related adverse events. However, little is known about the relationship in children in the emergency department (ED).

METHODS

This is an analysis of the data from 2 prospective, observational, multicenter registries of emergency airway management. The data were collected from consecutive patients who underwent emergency airway management in 19 EDs across Japan from March 2010 to November 2017. We included children 18 years or younger who underwent tracheal intubation in the ED. The primary exposure was the number of intubation attempts (1 vs ≥2). The primary outcome was an adverse event during or immediately after the intubation.

RESULTS

A total of 439 children were eligible for the analysis. Of 279 children with first-pass success, 24 children (9%) had an adverse event. By contrast, of 160 children with ≥2 intubation attempts, 50 children patients (31%) had an adverse event. In the unadjusted model, multiple intubation attempts were significantly associated with a higher rate of adverse events (unadjusted odds ratio, 4.83; 95% confidence interval, 2.57-9.06; P < 0.001). This association remained significant after adjusting for 7 potential confounders and patient clustering within the hospital (adjusted odds ratio, 4.49; 95% confidence interval, 2.36-8.53; P < 0.001). Similar associations were found across different age groups and among children without cardiac arrest (all, P < 0.05).

CONCLUSIONS

In this analysis of large prospective multicenter data, multiple intubation attempts were associated with a significantly higher rate of intubation-related adverse events in children in the ED.

Machine Learning Approaches for Predicting Difficult Airway and First-Pass Success in the Emergency Department: Multicenter Prospective Observational Study

Background

There is still room for improvement in the modified LEMON (look, evaluate, Mallampati, obstruction, neck mobility) criteria for difficult airway prediction and no prediction tool for first-pass success in the emergency department (ED).

Objective

We applied modern machine learning approaches to predict difficult airways and first-pass success.

Methods

In a multicenter prospective study that enrolled consecutive patients who underwent tracheal intubation in 13 EDs, we developed 7 machine learning models (eg, random forest model) using routinely collected data (eg, demographics, initial airway assessment). The outcomes were difficult airway and first-pass success. Model performance was evaluated using c-statistics, calibration slopes, and association measures (eg, sensitivity) in the test set (randomly selected 20% of the data). Their performance was compared with the modified LEMON criteria for difficult airway success and a logistic regression model for first-pass success.

Results

Of 10,741 patients who underwent intubation, 543 patients (5.1%) had a difficult airway, and 7690 patients (71.6%) had first-pass success. In predicting a difficult airway, machine learning models—except for k-point nearest neighbor and multilayer perceptron—had higher discrimination ability than the modified LEMON criteria (all, P≤.001). For example, the ensemble method had the highest c-statistic (0.74 vs 0.62 with the modified LEMON criteria; P<.001). Machine learning models—except k-point nearest neighbor and random forest models—had higher discrimination ability for first-pass success. In particular, the ensemble model had the highest c-statistic (0.81 vs 0.76 with the reference regression; P<.001).

Conclusions

Machine learning models demonstrated greater ability for predicting difficult airway and first-pass success in the ED.

Detection of Advanced Lesions of Atherosclerosis in Carotid Arteries Using 3-Dimensional Motion-Sensitized Driven-Equilibrium Prepared Rapid Gradient Echo (3D-MERGE) Magnetic Resonance Imaging as a Screening Tool

BACKGROUND AND PURPOSE

Two-dimensional high-resolution multicontrast magnetic resonance imaging (2D-MC MRI) is currently the most reliable and reproducible noninvasive carotid vessel wall imaging technique. However, the long scan time required for 2D-MC MRI restricts its practical clinical application. Alternatively, 3-dimensional motion-sensitized driven-equilibrium prepared rapid gradient echo (3D-MERGE) vessel wall MRI can provide high isotropic resolution with extensive coverage in two minutes. In this study, we sought to prove that 3D-MERGE alone can serve as a screening tool to identify advanced carotid lesions.

METHODS

Two hundred twenty-seven subjects suspected of recent ischemic stroke or transient ischemic attack were imaged using 2D-MC MRI with an imaging time of 30 minutes, then with 3D-MERGE with an imaging time of 2 minutes, on 3T-MRI scanners. Two experienced reviewers interpreted plaque components using 2D-MC MRI as the reference standard and categorized plaques using a modified American Heart Association lesion classification for MRI. Plaques of American Heart Association type IV and above were classified as advanced. Arteries of American Heart Association types I to II and III were categorized as normal or with early lesions, respectively. One radiologist independently reviewed only 3D-MERGE and labeled the plaques as advanced if they had a wall thickness of >2 mm with high or low signal intensity compared with the adjacent sternocleidomastoid muscle. Sensitivity, specificity, and accuracy for 3D-MERGE were calculated.

RESULTS

Four hundred forty-nine arteries from 227 participants (mean age 61.2 years old, 64% male) were included in the analysis. Sensitivity, specificity, and accuracy for identification of advanced lesions on 3D-MERGE were 95.0% (95% CI, 91.8-97.2), 86.9% (95% CI, 81.4-92.0), 93.8% (95% CI, 91.1-95.8), respectively.

CONCLUSIONS

3D-MERGE can accurately identify advanced carotid atherosclerotic plaques in patients suspected of stroke or transient ischemic attack. It has a more extensive coverage and higher sensitivity and specificity for advanced plaque detection with a much shorter acquisition time than 2D-MC MRI.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02017756.

Atherosclerotic Burden and Remodeling Patterns of the Popliteal Artery as Detected in the Magnetic Resonance Imaging Osteoarthritis Initiative Data Set

Background

An artificial intelligence vessel segmentation tool, Fully Automated and Robust Analysis Technique for Popliteal Artery Evaluation (FRAPPE), was used to analyze a large databank of popliteal arteries imaged through the OAI (Osteoarthritis Initiative) to study the impact of atherosclerosis risk factors on vessel dimensions and characterize remodeling patterns.

Methods and Results

Magnetic resonance images from 4668 subjects contributing 9189 popliteal arteries were analyzed using FRAPPE. Age ranged from 45 to 79 years (median, 61), and 58% were women. Mean lumen diameter, mean outer wall diameter, and mean wall thickness (MWT) were measured per artery. Their median values were 5.8 mm (interquartile range, 5.2–6.5 mm), 7.3 mm (interquartile range, 6.7–8.1 mm), and 0.78 mm (interquartile range, 0.73–0.84 mm) respectively. MWT was associated with multiple cardiovascular risk factors, with age (4.2% increase in MWT per 10‐year increase in age; 95% CI, 3.9%–4.5%) and sex (8.6% higher MWT in men than women; 95% CI, 7.7%–9.3%) being predominant. On average, lumen and outer wall diameters increased with increasing MWT until the thickness was 0.92 mm for men and 0.84 mm for women. After this point, lumen diameter decreased steadily, more rapidly in men than women (−7.9% versus −6.1% per 25% increase in MWT; P<0.001), with little change in outer wall diameter.

Conclusions

FRAPPE has enabled the analysis of the large OAI knee magnetic resonance imaging data set, successfully showing that popliteal atherosclerosis is predominantly associated with age and sex. The average vessel remodeling pattern consisted of an early phase of compensatory enlargement, followed by a negative remodeling, which is more pronounced in men.

Domain adaptive and fully automated carotid artery atherosclerotic lesion detection using an artificial intelligence approach (LATTE) on 3D MRI

PURPOSE

To develop and evaluate a domain adaptive and fully automated review workflow (lesion assessment through tracklet evaluation, LATTE) for assessment of atherosclerotic disease in 3D carotid MR vessel wall imaging (MR VWI).

METHODS

VWI of 279 subjects with carotid atherosclerosis were used to develop LATTE, mainly convolutional neural network (CNN)-based domain adaptive lesion classification after image quality assessment and artery of interest localization. Heterogeneity in test sets from various sites usually causes inferior CNN performance. With our novel unsupervised domain adaptation (DA), LATTE was designed to accurately classify arteries into normal arteries and early and advanced lesions without additional annotations on new datasets. VWI of 271 subjects from four datasets (eight sites) with slightly different imaging parameters/signal patterns were collected to assess the effectiveness of DA of LATTE using the area under the receiver operating characteristic curve (AUC) on all lesions and advanced lesions before and after DA.

RESULTS

LATTE had good performance with advanced/all lesion classification, with the AUC of >0.88/0.83, significant improvements from >0.82/0.80 if without DA.

CONCLUSIONS

LATTE can locate target arteries and distinguish carotid atherosclerotic lesions with consistently improved performance with DA on new datasets. It may be useful for carotid atherosclerosis detection and assessment on various clinical sites.

Computed tomography angiography findings predictive of post-intervention vasospasm in patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE

To evaluate the association of CT/CT angiography (CTA) findings and clinical characteristics with subsequent vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH).

METHODS-

Consecutive presentation CTA head exams in patients with aSAH between January 2005 and June 2015 were retrospectively evaluated for intracranial arterial calcification, undulation and non-calcified stenosis. Additional variables including modified Fisher Scale (mFS), Glasgow Coma Scale (GCS) and neurological exam status were reviewed. Associations of CTA findings with the incidence of angiographic vasospasm were assessed with multivariate logistic regression models using the least absolute shrinkage and selection operator machine-learning algorithm. Model performance was summarized using c-index with bootstrap optimism-adjustment.

RESULTS

Intracranial arterial calcification, seen in 51.7% of 195 total patients, was protective against vasospasm (OR-0.6; 95% CI-0.52-0.67; p = 0.009), while arterial undulation (24%) was associated with subsequent vasospasm (OR-2.6; 95% CI-1.3-5.1; p = 0.007). Non-calcified intracranial arterial stenosis (5%) was associated with subsequent vasospasm, (OR-4.7; 95% CI-1.0-22.8; p = 0.054). Least absolute shrinkage and selection operator selected all three CTA findings as predictors in a multivariate model for vasospasm in addition to clinical factors, which demonstrated superior predictive performance (c-index-0.74; 95% CI-0.69-0.82) compared to a model based on mFS and clinical factors only (c-index-0.66; 95% CI-0.57-0.75; p = 0.010 for the difference).

CONCLUSION

Presentation CTA findings combined with clinical factors may better predict the development of vasospasm in patients with aSAH compared to current prognostic models alone.

ADVANCES IN KNOWLEDGE

The combination of initial CT/CTA and clinical findings better predict development of vasospasm after aSAH. This can lead to better markers for use in future clinical trials to develop vasospasm preventative treatments and potentially provide better targets for early aggressive treatment.

Association of advanced age with intubation-related adverse events in the emergency department: a multicentre prospective observational study

BACKGROUND

While the older population accounts for an increasing proportion of emergency department (ED), little is known about intubation-related adverse events in this high-risk population. We sought to determine whether advanced age is associated with a higher risk of intubation-related adverse events in the ED.

METHODS

This is an analysis of data from a prospective, 15-centre, observational study-the second Japanese Emergency Airway Network (JEAN-2) study. The current analysis included adult (aged ≥18 years) patients who underwent intubation in the ED between 2012 and 2018. The primary exposure was age (18-39, 40-64, 65-74, 75-84 and ≥85 years). The primary outcome was overall intubation-related adverse events during or immediately after an intubation. Adverse events were further categorised into major (hypotension, hypoxaemia, oesophageal intubation, cardiac arrest, dysrhythmia and death) and minor (endobronchial intubation, oesophageal intubation with early recognition, dental/lip trauma, airway trauma and regurgitation) adverse events. We constructed multivariable logistic regression models adjusting for seven potential confounders with generalised estimating equations that account for patients clustering within the ED.

RESULTS

Among 9714 patients eligible for the analysis, 15% were aged ≥85 years, and 16% had adverse events. In the unadjusted models, advanced age was not significantly associated with the risk of overall adverse events. In the adjusted models, the association was significant (adjusted OR 1.41 in age ≥85 years (95% CI, 1.09 to 1.81) compared with age 18-39 years). Specifically, older patients had a significantly higher risk of major adverse events (adjusted OR in age ≥85 years 2.65 (95% CI, 1.78 to 3.94)), which was driven by the association of advanced age with an increased risk of hypotension (adjusted OR in ≥85 years, 5.69 (95% CI, 3.13 to 10.37)). By contrast, advanced age was not associated with minor adverse events.

CONCLUSION

Based on the data from a prospective multicentre study, advanced age was associated with higher risks of major adverse events.

Bilaterally Asymmetric Associations Between Extracranial Carotid Artery Atherosclerosis and Ipsilateral Middle Cerebral Artery Stenosis in Symptomatic Patients: A CARE-II Study

OBJECTIVE

To determine the bilaterally asymmetrical associations between extracranial carotid artery atherosclerosis and ipsilateral middle cerebral artery (MCA) stenosis in symptomatic patients using magnetic resonance vessel wall imaging. Approach and Results: Patients with symptomatic carotid artery atherosclerosis were recruited from the Chinese Atherosclerosis Risk Evaluation, a multicenter study. All subjects underwent intracranial magnetic resonance angiography and extracranial carotid artery magnetic resonance imaging. Severe stenosis (stenosis ≥50%) of MCA, carotid moderate-to-severe stenosis (stenosis ≥50%), plaque compositions, and high-risk plaque on symptomatic side were evaluated in all subjects. Associations between ipsilateral MCA stenosis and extracranial carotid plaque features were evaluated. A total of 363 patients (mean age: 61.2±10.4 years old; 254 males) were included. In the left symptomatic cerebrovascular group (n=186), carotid moderate-to-severe stenosis (odds ratio [OR], 3.00 [95% CI, 1.03-8.79]; P=0.045), intraplaque hemorrhage (OR, 3.68 [95% CI, 1.21-11.19]; P=0.021), fibrous cap rupture (OR, 5.70 [95% CI, 1.60-20.31]; P=0.007), and high-risk plaque (OR, 2.95 [95% CI, 1.19-7.35]; P=0.020) were significantly associated with ipsilateral severe MCA stenosis, after adjusting for confounding factors. In the right symptomatic cerebrovascular group (n=177), severe MCA stenosis was significantly associated with ipsilateral carotid moderate-to-severe stenosis (OR, 3.98 [95% CI, 1.54-10.32]; P=0.004) but not with other extracranial carotid plaque features (all P>0.05), after adjusting for confounding factors.

CONCLUSIONS

In the symptomatic arteries, vulnerable plaque features are independently associated with ipsilateral severe MCA stenosis on the left side, but this association is not found on the right side, indicating the associations of atherosclerotic disease between intracranial and extracranial carotid arteries are asymmetrical.

Fully automated and robust analysis technique for popliteal artery vessel wall evaluation (FRAPPE) using neural network models from standardized knee MRI

PURPOSE

To develop a fully automated vessel wall (VW) analysis workflow (fully automated and robust analysis technique for popliteal artery evaluation, FRAPPE) on the popliteal artery in standardized knee MR images.

METHODS

Popliteal artery locations were detected from each MR slice by a deep neural network model and connected into a 3D artery centerline. Vessel wall regions around the centerline were then segmented using another neural network model for segmentation in polar coordinate system. Contours from vessel wall segmentations were used for vascular feature calculation, such as mean wall thickness and wall area. A transfer learning and active learning framework was applied in training the localization and segmentation neural network models to maintain accuracy while reducing manual annotations. This new popliteal artery analysis technique (FRAPPE) was validated against manual segmentation qualitatively and quantitatively in a series of 225 cases from the Osteoarthritis Initiative (OAI) dataset.

RESULTS

FRAPPE demonstrated high accuracy and robustness in locating popliteal arteries, segmenting artery walls, and quantifying arterial features. Qualitative evaluations showed 1.2% of slices had noticeable major errors, including segmenting the wrong target and irregular vessel wall contours. The mean Dice similarity coefficient with manual segmentation was 0.79, which is comparable to inter-rater variations. Repeatability evaluations show most of the vascular features have good to excellent repeatability from repeated scans of same subjects, with intra-class coefficient ranging from 0.80 to 0.98.

CONCLUSION

This technique can be used in large population-based studies, such as OAI, to efficiently assess the burden of atherosclerosis from routine MR knee scans.

Differences in atheroma between Caucasian and Asian subjects with anterior stroke: A vessel wall MRI study

Background and purpose

While extracranial carotid artery stenosis is more common among Caucasians and intracranial artery stenosis is more common among Asians, the differences in atherosclerotic plaque characteristics have not yet been extensively examined. We sought to investigate plaque location and characteristics within extracranial carotid and intracranial arteries in symptomatic Caucasians and Chinese using vessel wall MRI.

Methods

Subjects with recent anterior circulation ischaemic stroke were recruited and imaged at two sites in the USA and China using similar protocols. Both extracranial carotid and intracranial arteries were reviewed to determine plaque location and characteristics.

Results

The prevalence of extracranial carotid plaque in Caucasians and Chinese was 73.1% and 49.1%, respectively (p=0.055). Prevalence of intracranial plaque was 38.5% and 69.1% in Caucasians and Chinese, respectively (p=0.02). Furthermore, 42% of Caucasians and 16% of Chinese had high-risk plaque (HRP) features (intraplaque haemorrhage, luminal surface disruption) in the extracranial carotid artery (p=0.03). The prevalence of HRP features in intracranial arteries was not significantly different between the two cohorts (4% vs 11%; p=0.42).

Conclusions

Differences in the location and characteristics of cerebrovascular atherosclerosis were identified by vessel wall MRI in US Caucasian and Chinese subjects with recent anterior circulation ischaemic stroke. Extracranial carotid plaques with HRP features were more common in Caucasians. Intracranial plaques were more common in Chinese subjects, but no significant difference between the two cohorts in intracranial HRP prevalence was found. Larger studies using vessel wall imaging to investigate racial differences in cerebrovascular disease may inform underlying mechanisms of HRP development and may ultimately help guide appropriate therapy.

Comparison of carotid atherosclerotic plaques between subjects in Northern and Southern China: a Chinese atherosclerosis risk evaluation study

Background and purpose

To investigate differences in the characteristics of carotid atherosclerotic plaques of symptomatic subjects in northern and southern China using MRI.

Methods

Sixty-three subjects in northern China (mean age: 59.1±8.6 years, 45 men) and 56 subjects in southern China (mean age: 60.4±8.6 years, 38 men) were included. All subjects underwent carotid artery multicontrast vessel wall MRI. Plaque morphology, calcification, lipid-rich necrotic core, intraplaque haemorrhage, luminal surface disruption and high-risk plaque were measured and identified. All plaque characteristics were compared between subjects in northern and southern China using Mann-Whitney U test or χ² test.

Results

Compared with subjects in southern China, those in northern China had significantly greater areas for lumen (57.7±14.9 mm² vs 50.4±18.3 mm², p=0.009), wall (38.4±13.1 mm² vs 31.9±11.7 mm², p<0.001) and total vessel (96.1±20.2 mm² vs 82.4±22.7 mm², p=0.001) and mean wall thickness (1.25±0.43 mm vs 1.13±0.40 mm, p=0.019). χ² analysis showed that subjects in northern China tended to have a higher prevalence of intraplaque haemorrhage (14.3% vs 5.4%, p=0.106) and high-risk plaque (20.6% vs 10.7%, p=0.140) than those in southern China, although these differences were not statistically significant (all p>0.05).

Conclusion

Subjects in northern China have significantly larger vessel size and may have a higher prevalence of vulnerable plaques than those in southern China. Our findings provide additional perspective to optimise the management of cerebrovascular disease in individuals in different regions in China.

Trial registration number

NCT02017756

Association Between Carotid Bifurcation Geometry and Atherosclerotic Plaque Vulnerability: A Chinese Atherosclerosis Risk Evaluation Study

OBJECTIVE

Carotid bifurcation geometry has been believed to be a risk factor for the initiation of atherosclerosis because of its influence on hemodynamics. However, the relationships between carotid bifurcation geometry and plaque vulnerability are not fully understood. This study aimed to determine the association between carotid bifurcation geometry and plaque vulnerability using magnetic resonance vessel wall imaging. Approach and Results: A total of 501 carotid arteries with nonstenotic atherosclerosis were included from the cross-sectional, multicenter CARE II study (Chinese Atherosclerosis Risk Evaluation). Four standardized carotid bifurcation geometric parameters (bifurcation angle, internal carotid artery planarity, luminal expansion FlareA, and tortuosity Tort2D) were derived from time-of-flight magnetic resonance angiography. Presence of vulnerable plaque, which was characterized by intraplaque hemorrhage, large lipid-rich necrotic core, or disrupted luminal surface, was determined based on multicontrast carotid magnetic resonance vessel wall images. Vulnerable plaques (N=43) were found to occur at more distal locations (ie, near the level of flow divider) than stable plaques (N=458). Multivariable logistic regression showed that the luminal expansion FlareA (odds ratio, 0.45 [95% CI, 0.25-0.81]; P=0.008) was associated with plaque vulnerability after adjustment for age, sex, maximum wall thickness, plaque location, and other geometric parameters.

CONCLUSIONS

Smaller luminal expansion at carotid bifurcation is associated with vulnerable plaque. The finding needs to be verified with longitudinal studies and the underlying mechanism should be further explored with hemodynamics measurement in the future.

Differences in Carotid Plaques Between Symptomatic Patients With and Without Diabetes Mellitus

Objective- Diabetes mellitus is associated with high-risk atherosclerotic plaques. This study aimed to compare characteristics of carotid atherosclerotic plaques in symptomatic Chinese diabetic and nondiabetic patients using vessel wall magnetic resonance imaging. Approach and Results- Patients with cerebral ischemic symptoms in the anterior circulation and carotid atherosclerotic plaque determined by ultrasound were recruited from a cross-sectional, observational, multicenter study of CARE-II (Chinese Atherosclerosis Risk Evaluation). All patients underwent magnetic resonance imaging for carotid arteries. The morphological and compositional characteristics of carotid plaques were compared between diabetic and nondiabetic patients using linear (continuous variables) and logistic regression (binary variables). In a total of 584 recruited patients, 182 (31.2%) had diabetes mellitus. From the univariate analysis, diabetic patients had significantly greater mean wall area (33.7 versus 31.1 mm²; P=0.002), maximum wall thickness (3.2 versus 2.8 mm; P<0.001), and mean normalized wall index (43.8% versus 41.0%; P<0.001) and had significantly higher prevalence of calcification (51.6% versus 36.6%; P=0.001), lipid-rich necrotic core (77.5% versus 58.5%; P<0.001), and high-risk plaque (29.7% versus 19.9%; P=0.011) than nondiabetic patients. After adjusting for clinical characteristics, the differences in presence of calcification ( P=0.018) and lipid-rich necrotic core ( P=0.001) remained statistically significant. Conclusions- Symptomatic Chinese diabetic patients are more likely to have carotid plaques with calcification and lipid-rich necrotic core than nondiabetic patients, suggesting that diabetic patients may develop more severe atherosclerotic disease that should be accounted for in their clinical management.

Understanding Atherosclerosis Through an Osteoarthritis Data Set

Atherosclerotic cardiovascular disease remains a worldwide epidemic and one of the leading causes of death nowadays. Vessel wall imaging can be used to understand the development and progression of atherosclerosis, but it is rarely done because of the high cost. We recently identified the Osteoarthritis Initiative, a large prospective cohort study of knee osteoarthritis, which might serve as a valuable source for atherosclerosis research with its serial knee magnetic resonance imaging data. We have found that these images are suitable for vessel wall image analysis of the lower extremity arteries. Here, we will introduce the Osteoarthritis Initiative data set and explain why it could be used for cardiovascular research purposes. Also, we will briefly comment on peripheral artery atherosclerosis as it is covered in the Osteoarthritis Initiative image data set and review the use of vessel wall imaging for studying atherosclerosis. We think data mining of imaging studies, not originally designed on cardiovascular research, can not only maximize the value of the imaging data set but also boost our understanding of atherosclerosis.

Characterization of Carotid Atherosclerotic Plaques Using 3-Dimensional MERGE Magnetic Resonance Imaging and Correlation With Stroke Risk Factors

Background and Purpose- High-resolution magnetic resonance imaging is capable of characterizing carotid atherosclerotic plaque morphology and composition. Most reported carotid plaque imaging techniques are 2-dimensional (2D) based with limited longitudinal coverage of ≈30 mm, which may be insufficient for complete visualization of extracranial carotid atheroma. A 3D black-blood imaging technique, motion-sensitized driven equilibrium prepared rapid gradient echo technique (3D-MERGE) can provide larger coverage. We sought to use 3D-MERGE to investigate carotid atherosclerosis plaque distribution and to analyze their correlation with clinical information and stroke risk factors. Methods- From 5 hospitals in China, 97 subjects suspected of recent stroke or transient ischemic attack were imaged with 3D-MERGE within 2 weeks of symptoms using 3T magnetic resonance imaging. Images were analyzed by 2 reviewers. Plaque length was calculated and categorized as plaques within, partially outside, or completely outside of typical 2D magnetic resonance imaging coverage. Associations between plaque features and clinical information, stroke risk factors were assessed. Results- Ninety-seven subjects with 194 carotid arteries (70 men and 27 women, mean age 60 years) were analyzed. Of the 136 plaques identified, 68 (50%) were within, 46 (33.8%) were partially outside, and 22 (16.2%) were completely outside of 2D magnetic resonance imaging coverage. Total plaque length was significantly positively associated with male sex (P<0.001), hypertension (P=0.011), and history of smoking (P<0.001). Hypertensive subjects were more likely to have at least one plaque completely outside the 2D magnetic resonance imaging coverage than nonhypertensive subjects (P=0.007). Conclusions- The 3D-MERGE allows for the identification of substantially more carotid plaques than 2D black-blood techniques. The extent and distribution of plaque, identified by the larger coverage afforded by 3D-MERGE, were found to correlate significantly with male sex and risk factors that are common among patients with stroke, including hypertension and history of cigarette smoking.

Factors associated with successful rescue intubation attempts in the emergency department: an analysis of multicenter prospective observational study in Japan

Aim

It remains unclear whether physicians should change intubation approaches after the failed first attempt. We aimed to determine the rescue intervention approaches associated with a higher success rate at the second attempt in the emergency department (ED).

Methods

We analyzed the data from a prospective, multicenter, observational study – the second Japanese Emergency Airway Network Study. The current analysis included all patients who underwent emergency intubation from February 2012 through November 2017. We defined a rescue intubation attempt as a second intubation attempt with any change in intubation approaches (i.e., change in methods, devices, or intubators) from the failed first attempt. The outcome measure was second‐attempt success.

Results

Of 2,710 patients with a failed first attempt, 43% underwent a second intubation attempt with changes in intubation approach (i.e., rescue intubation). Rescue intubation attempts were associated with a higher second‐attempt success rate compared to non‐rescue intubation attempts (adjusted odds ratio [OR], 1.78; 95% confidence interval [CI], 1.50–2.12). The rescue intubation approaches associated with a higher second‐attempt success were changes from non‐rapid sequence intubation (RSI) to RSI (adjusted OR, 2.04; 95% CI, 1.12–3.75), from non‐emergency medicine (EM) residents to EM residents (adjusted OR, 2.02; 95% CI, 1.44–2.82), and from non‐EM attending physicians to EM attending physicians (adjusted OR, 2.82; 95% CI, 2.14–3.71).

Conclusions

In this large multicenter study, rescue interventions were associated with a higher second‐attempt success rate. The data also support the use of RSI and backup by EM residents or EM attending physicians to improve the airway management performance after a failed attempt in the ED.

Four Different Carotid Atherosclerotic Behaviors Based on Luminal Stenosis and Plaque Characteristics in Symptomatic Patients: An in Vivo Study

Correct stratification of ischemic stroke risk allows for the proper treatment of carotid atherosclerotic disease. We seek to differentiate plaque types based on stenosis level and plaque morphology. The Chinese Atherosclerosis Risk Evaluation (CARE-II) study is a cross-sectional, observational, multicenter study to assess carotid atherosclerotic plaques in symptomatic subjects using vessel wall magnetic resonance imaging. Plaque morphology and presence of plaque components were reviewed using multi-contrast magnetic resonance imaging. The carotid arteries were divided into four groups based on stenosis level and plaque components. Out of 1072 ischemic stroke subjects, 452 ipsilateral side carotid arteries were included. Significant stenosis (SS) (≥50% stenosis) with high-risk plaque (HRP) features was present in 37 arteries (8.2%), SS(+)/HRP(-) in 29 arteries (6.4%), SS(-)/HRP(+) in 57 arteries (12.6%), and SS(-)/HRP(-) in 329 arteries (72.8%). The prevalence of SS(-)/HRP(+) arteries in this cohort was substantial and had greater wall thickness than the SS(+)/HRP(-) group. These arteries may be misclassified for carotid revascularization by current guidelines based on the degree of luminal stenosis only. These findings have implications for further studies to assess stroke risk using vessel wall imaging.

Advancing emergency airway management practice and research

Emergency airway management is one of the vital resuscitative procedures undertaken in the emergency department (ED). Despite its clinical and research importance in the care of critically ill and injured patients, earlier studies have documented suboptimal intubation performance and high adverse event rates with a wide variation across the EDs. The optimal emergency airway management strategies remain to be established and their dissemination to the entire nation is a challenging task. This article reviews the current published works on emergency airway management with a focus on the use of airway management algorithms as well as the importance of first‐pass success and systematic use of rescue intubation strategies. Additionally, the review summarizes the current evidence for each of the important airway management processes, such as assessment of the difficult airway, preparation (e.g., positioning and oxygenation), intubation methods (e.g., rapid sequence intubation), medications (e.g., premedications, sedatives, and neuromuscular blockades), devices (e.g., direct and video laryngoscopy and supraglottic devises), and rescue intubation strategies (e.g., airway adjuncts and rescue intubators), as well as the airway management in distinct patient populations (i.e., trauma, cardiac arrest, and pediatric patients). Well‐designed, rigorously conducted, multicenter studies that prospectively and comprehensively characterize emergency airway management should provide clinicians with important opportunities for improving the quality and safety of airway management practice. Such data will not only advance research into the determination of optimal airway management strategies but also facilitate the development of clinical guidelines, which will, in turn, improve the outcomes of critically ill and injured patients in the ED.

Methylxanthine use for acute asthma in the emergency department in Japan: a multicenter observational study

Aim

Methylxanthines are no longer recommended for emergency department (ED) patients with acute asthma according to international guidelines. We aimed to describe the current methylxanthine use for acute asthma and to determine factors related to its use in the ED.

Methods

We undertook a multicenter retrospective study in 23 EDs across Japan. From each participating hospital, we randomly identified 60 ED patients aged 18-54 years with acute asthma from 2009 through 2011. We examined the associations of ED and patient characteristics with methylxanthine use by constructing a multivariable logistic regression model adjusting for a predefined set of ED- and patient-level factors.

Results

Among 1,380 patients, methylxanthines were used for 79 patients (5.7%, 95% confidence interval [CI], 4.6-7.0%). The proportion of methylxanthine treatment varied substantially among EDs, ranging from 0% to 26.1%. In the multivariable analysis, the number of annual ED patients with acute asthma (odds ratio [OR] per 100 increase in annual asthma patients, 0.12; 95% CI, 0.04-0.34; P < 0.001) and having a protocol for asthma treatment (OR 2.91; 95% CI, 1.06-8.00; P = 0.04) at the ED level, and systemic corticosteroid use (OR 6.39; 95% CI, 3.34-12.22; P < 0.001) at the patient level were associated with likelihood of methylxanthine use.

Conclusions

In this multicenter study, approximately 6% of ED patients with acute asthma were treated with methylxanthines, with a wide variation across EDs. The number of annual ED patients with acute asthma was significantly associated with a lower likelihood of methylxanthine use, whereas having an ED asthma treatment protocol and systemic corticosteroid use in the ED were associated with a higher likelihood of methylxanthine treatment.

Inter-rater and scan-rescan reproducibility of the detection of intracranial atherosclerosis on contrast-enhanced 3D vessel wall MRI

OBJECTIVE

The objective is to establish interscan, inter- and intra-rater reproducibility of a multicontrast three-dimensional contrast-enhanced intracranial vessel wall (IVW) MRI protocol with 0.6 mm acquired (0.3 mm interpolated) isotropic resolution in the detection of intracranial atherosclerosis.

METHODS

Subjects with established intracranial atherosclerosis were prospectively recruited and underwent two contrast-enhanced three-dimensional IVW scans within a 2-week period. Four raters with varying degrees of vessel wall imaging interpretation experience, through an iterative training process developed guidelines for plaque identification with no, possible and definite plaque categories. Using these guidelines, the raters reviewed the cases in pairs (consensus rating), while blinded to the interpretations of the other pair, clinical reports and patient history. The rater pairs reviewed 19 segments per patient for the presence and location of atherosclerotic plaques. Inter-scan, inter rater and intra rater reproducibility were assessed.

RESULTS

19 subjects were scanned twice, with 361 total segments reviewed and 304-324 evaluable segments analyzed in the different reproducibility assessments. Overall inter-rater agreement for possible and definite plaque was 88.9 % [κ = 0.73; 95% confidence interval (CI) (0.62-0.81)], inter-scan/intra-rater agreement was 82.1 % [κ = 0.58; 95% CI (0.48-0.70)] and inter-scan/inter-rater agreement of 84.5% [κ = 0.64; 95% CI (0.51 - 0.76)].

CONCLUSION

Contrast-enhanced IVW imaging, with the utilization of detailed plaque definition guidelines for image review, can be a reproducible technique for the evaluation of intracranial atherosclerosis.

ADVANCES IN KNOWLEDGE

This work is the first to establish reproducibility of IVW for plaque identification with and without contrast. Reproducibility using contrast is important as most IVW applications rely on lesion enhancement.

The incidence of post-intubation hypertension and association with repeated intubation attempts in the emergency department

BACKGROUND

Studies in the non-emergency department (ED) settings have reported the relationships of post-intubation hypertension with poor patient outcomes. While ED-based studies have examined post-intubation hypotension and its sequelae, little is known about, post-intubation hypertension and its risk factors in the ED settings. In this context, we aimed to identify the incidence of post-intubation hypertension in the ED, and to test the hypothesis that repeated intubation attempts are associated with an increased risk of post-intubation hypertension.

METHODS

This study is a secondary analysis of the data from a multicenter prospective observational study of emergency intubations in 15 EDs from 2012 through 2016. The analytic cohort comprised all adult non-cardiac-arrest patients undergoing orotracheal intubation without pre-intubation hypotension. The primary exposure was the repeated intubation attempts, defined as ≥2 laryngoscopic attempts. The outcome was post-intubation hypertension defined as an increase in systolic blood pressure (sBP) of >20% along with a post-intubation sBP of >160 mmHg. To investigate the association of repeated intubation attempts with the risk of post-intubation hypertension, we fit multivariable logistic regression models adjusting for ten potential confounders and patient clustering within the EDs.

RESULTS

Of 3,097 patients, the median age was 69 years, 1,977 (64.0%) were men, and 991 (32.0%) underwent repeated intubation attempts. Post-intubation hypertension was observed in 276 (8.9%). In the unadjusted model, the incidence of post-intubation hypertension did not differ between the patients with single intubation attempt and those with repeated attempts (8.5% versus 9.8%, unadjusted P = 0.24). By contrast, after adjusting for potential confounders and patient clustering in the random-effects model, the patients who underwent repeated intubation attempts had a significantly higher risk of post-intubation hypertension (OR, 1.56; 95% CI, 1.11-2.18; adjusted P = 0.01).

CONCLUSIONS

We found that 8.9% of patients developed post-intubation hypertension, and that repeated intubation attempts were significantly associated with a significantly higher risk of post-intubation hypertension in the ED.

Abstract 184: The Relationship Between Carotid Plaque on Magnetic Resonance Plaque Imaging and Time From Stroke Onset

Introduction: Previous studies report that rate of recurrent stroke, as well as the risk of carotid surgery, is highest in the early stages following cerebral infarction and decreases over time, which suggests a process of plaque healing and stabilization. The purpose of this study is to identify differences in carotid plaque components according to the time from stroke onset, using carotid magnetic resonance plaque imaging (MRPI) to evaluate the dynamic phase of plaque development following an acute cerebrovascular ischemic event.Methods and

Results: MRPI on 3T scanners was obtained in 128 patients enrolled in the Carotid Artery Stenting study (MRCAS). MRCAS is a non-randomized multicenter prospective observational study to compare the plaque characteristics evaluated by MRI and ischemic complications after CAS in Japan. Among the 128 subjects, 60 presented with TIA or stroke and 68 were asymptomatic. The 60 TIA/stroke cases were classified into four groups based on the interval from the onset of symptoms to the date of carotid MRPI (Group 1: <14 days [n=25]; Group 2: 15-30 days[n=13]; and Group 3: >31 days [n=22]). The 68 asymptomatic cases were classified as Group 4. The volume of intraplaque hemorrhage (IPH), necrotic core, calcification and loose matrix was quantified on MRPI using Radiant DICOM viewer. Further, the presence of inner Loose Matrix (iLM) was identified as a high intensity area located between the vessel lumen and necrotic core or IPH on both T2WI and proton density weighted images.Patients characteristics were not significantly different among all groups. The mean volume of loose matrix in Group 3 was significantly lower than Group 1 and Group 4 (0 mm3 vs 12.3 mm3 and 15.5 mm3; p= 0.01, 0.03, respectively). The prevalence of iLM in Group 1 was higher than in Group 3 and 4 (68% vs 18.2%, 38.3% ; p<0.01, <0.01, respectively).

Conclusions: The prevalence of inner Loose Matrix, located at the interface between the lumen surface and the necrotic core or IPH, is significantly higher in the early stage after stoke/TIA. This study suggests that carotid plaques undergo rapid evolution, especially adjacent to the luminal surface, after an acute cerebrovascular ischemic event.

Abstract TP541: CT Angiography Leptomeningeal Collateral Assessment for Vasospasm in Patients With Aneurysmal Subarachnoid Hemorrhage

Introduction: Although leptomeningeal collaterals in acute large vessel occlusion have been well studied with respect to core infarct volume and risk of hemorrhagic conversion, their association with vasospasm in the setting of subarachnoid hemorrhage is less clear. Our purpose is to investigate the utility of leptomeningeal collateral scoring on CTA of patients presenting with aneurysmal subarachnoid hemorrhage (aSAH).

Methods: IRB-approved retrospective review of 122 consecutive patients with angiographic vasospasm after surgical or endovascular repair of ruptured intracranial aneurysm. A 5-point grading scale was adapted from Christoforidis et al. to compare leptomeningeal collateral scores on CTA with digital subtraction agiography (DSA) at presentation. An independent chart review was performed to correlate imaging with clinical markers of symptomatic vasospasm and delayed cerebral ischemia.

Results: Of the 122 initial patients with vasospasm, 16 demonstrated unilateral high-grade M1 stenosis in the absence of a second ipsilateral large vessel stenosis, 11 of which (68.8%) developed cerebral infarction secondary to vasospasm. Leptomeningeal collateral scoring on CTA at presentation agreed with DSA scores in half of patients (n=8), underestimated collaterals by 1 point in 7 patients, and overestimated their presence by 1 point in a single case.

Conclusion: Characterization of leptomeningeal collaterals in patients with aSAH may better predict subsequent vasospasm and cerebral ischemia. Our initial findings in cases of isolated severe M1 vasospasm highlight the potential value of collateral scoring on CTA at presentation. Collateral scoring on CTA correlates with DSA in half of cases, however further work is indicated to elucidate the technical factors contributing to 1-point underestimation in the other half cases. Christoforidis, G.A., et al., Predictors of hemorrhage following intra-arterial thrombolysis for acute ischemic stroke: the role of pial collateral formation. AJNR Am J Neuroradiol, 2009. 30 (1): p. 165-70.

Intracranial aneurysms at higher clinical risk for rupture demonstrate increased wall enhancement and thinning on multicontrast 3D vessel wall MRI

OBJECTIVE:

Identification of aneurysms at risk for rupture is important and challenging. We sought to evaluate if intracranial vessel wall (IVW) imaging characteristics of unruptured aneurysms correlate with clinical risk factors for rupture.

METHODS:

Patients with unruptured intracranial aneurysms were prospectively recruited and underwent a multi contrast 3D IVW protocol between April 6, 2016 and August 29, 2017. Two independent raters, blinded to aneurysm vulnerability, evaluated each aneurysm for wall enhancement, extent of enhancement in terms of the numbers of quadrants enhancing circumferentially, intensity of enhancement, and qualitative wall thinning. PHASES score was calculated for each aneurysm. Univariate logistic regression analysis was used to compare IVW characteristics between aneurysms at higher clinical risk for rupture (PHASES score > 3) and lower clinical risk for rupture (PHASES score ≤ 3).

RESULTS:

45 patients with 65 unruptured aneurysms were analyzed; 38 aneurysms with PHASES score > 3 (58%) and 27 aneurysms with PHASES score ≤ 3 (42%). Aneurysms with PHASES score > 3 were more likely to demonstrate enhancement (42.1% vs 14.8%, p = 0.022), greater extent of enhancement (mean: 2.9 vs 2.2 quadrants, p = 0.063), and wall thinning (9.2% vs 0%, p = 0.044). Inter-reader agreement was moderate-to-good for the presence (κ = 0.64), extent (κ = 0.64), and intensity of enhancement (κ = 0.60) but relatively low for wall thinning (κ = 0.25).

CONCLUSION:

Aneurysms at higher risk of rupture by PHASES score are more likely to demonstrate wall enhancement, more diffuse enhancement, and wall thinning on IVW.

ADVANCES IN KNOWLEDGE:

This study prospectively compares IVW-detected wall enhancement and thinning between unruptured aneurysms stratified into high and low risk groups by clinical scores (PHASES) of vulnerability.

Geriatric Nutritional Risk Index for independent walking function in maintenance hemodialysis patients: A single-facility retrospective cohort study

AIM

The target Geriatric Nutritional Risk Index (GNRI) for patients on chronic maintenance hemodialysis is unclear. We aimed to determine the relationship between the GNRI and independent walking ability in such patients.

METHODS

In the present retrospective cohort study, 90 patients receiving chronic maintenance hemodialysis were included. Logistic regression analyses were carried out to evaluate the relationship between the GNRI and independent walking ability. Receiver operating characteristic curve analysis was carried out to determine the cut-off GNRI for predicting independent walking ability.

RESULTS

Multivariate logistic regression analysis showed significant differences in age (odds ratio [OR] 0.8, 95% confidence interval [CI] 0.6-0.9), creatinine generation rate percentage (OR 1.1, 95% CI 1.0-1.2), GNRI (OR 1.4, 95% CI 1.1-1.8; P < 0.01) and urea removal rate (OR 0.3, 95% CI 0.1-0.9; P < 0.05). The cut-off GNRI for independent walking ability was 86.7 (area under the curve 0.80, sensitivity 92.1%, specificity 66.7%, positive hit ratio 86.6%, negative hit ratio 78.3%). The factors correlated with survival in the univariate analysis were the GNRI, equilibrated Kt/V, urea removal rate, clear space rate, salt intake amount (P < 0.01), number of days of hospitalization and %creatinine generation rate (P < 0.05). The Cox proportional hazard regression model showed an OR of 0.77 (95% CI 0.32-1.8) at a GNRI <86/GNRI ≥86. In the multivariate survival analysis, we observed no significant differences in any of the factors.

CONCLUSIONS

GNRI was correlated with walking ability, which indicated that GNRI might predict future walking ability; also, a GNRI of 87 might be the target for maintaining walking ability. Geriatr Gerontol Int 2018; 18: 1556-1561.

Association of fentanyl use in rapid sequence intubation with post-intubation hypotension

BACKGROUND

The anesthesia literature has reported that pre-intubation fentanyl use is associated with post-intubation hypotension which is a risk factor of poor post-emergency department (ED) prognosis. However, little is known about the relations between fentanyl use for intubation and post-intubation hypotension in the ED. We aimed to determine whether pretreatment with fentanyl was associated with a higher risk of post-intubation hypotension in the ED.

METHODS

We conducted a secondary analysis of data of ED airway management collected from a multicenter prospective study of 14 Japanese EDs from February 2012 through November 2016. We included all adult non-cardiac-arrest patients who underwent rapid sequence intubation for medical indication. Patients were divided into fentanyl and non-fentanyl groups. The primary outcome was post-intubation hypotension (systolic blood pressure ≤90mmHg) in the ED.

RESULTS

Of 1263 eligible patients, 466 (37%) patients underwent pretreatment with fentanyl. The fentanyl group had a higher risk of post-intubation hypotension (17% vs. 6%; unadjusted OR, 1.73; 95%CI, 1.01-2.97; P=0.048) compared to the non-fentanyl group. In the multivariable analysis adjusting for age, sex, weight, principal indication, sedatives, intubator's specialty, number of intubation attempts, and patient clustering within EDs, the fentanyl group had a higher risk of post-intubation hypotension (adjusted OR, 1.87; 95%CI, 1.05-3.34; P=0.03) compared to the non-fentanyl group. In the sensitivity analysis using propensity score matching, this association remained significant (OR, 3.17; 95%CI, 1.96-5.14; P<0.01).

CONCLUSION

In this prospective multicenter study of ED airway management, pretreatment with fentanyl in rapid sequence intubation was associated with higher risks of post-intubation hypotension.

Carotid Artery Remodeling Is Segment Specific: An In Vivo Study by Vessel Wall Magnetic Resonance Imaging

OBJECTIVE

Early atherosclerosis is often undetected due in part to compensatory enlargement of the outer wall, termed positive remodeling. Variations in hemodynamic conditions and clinical factors influence the patterns of remodeling. The carotid artery provides an opportunity to examine these variations because of the unique geometry of the carotid bulb. This study aimed to determine differences in remodeling of the common, internal, and bifurcation segments of the carotid using magnetic resonance imaging.

APPROACH AND RESULTS

Carotid arteries of 525 subjects without history of cardiovascular disease were imaged by magnetic resonance imaging. The carotid artery was divided into 3 segments: common carotid artery; bifurcation; and internal carotid artery. Remodeling patterns were characterized using linear regression analysis of lumen and total vessel areas (dependent variables) compared with maximum wall thickness (independent variable) for each segment, adjusted for age, sex, and height. The common carotid artery demonstrated a pattern consistent with positive remodeling, whereas the bifurcation demonstrated negative remodeling. The internal carotid artery demonstrated a mixed pattern of outer wall expansion and lumen constriction. Females and subjects with diabetes mellitus showed more positive remodeling, hypertension was associated with attenuated positive remodeling, and those with hypercholesterolemia showed more negative remodeling.

CONCLUSIONS

In this cohort of 55- to 80-year-old individuals without history of cardiovascular disease, the pattern of early carotid artery remodeling was segment specific and appeared to be associated with sex and clinical characteristics. These findings provide the groundwork for longitudinal studies to define local and systemic factors such as hemodynamic and clinical conditions on carotid artery remodeling.

Abstract WP135: Location and Composition of Extracranial Carotid and Intracranial Atheroma in Symptomatic U.S. and Chinese Patients Detected by Vessel Wall Magnetic Resonance Imaging

Introduction: Atherosclerosis of the extracranial carotid and intracranial arteries is an important contributor to stroke. Autopsy studies suggest that the location and components of atheroma may vary between different ethnic groups. Advances in cerebrovascular vessel wall imaging with 3D-magnetic resonance imaging (MRI) have provided a critical tool to assess these differences in vivo .

Hypothesis: We tested the hypothesis that carotid culprit plaques are more common in U.S. patients, and that intracranial culprit plaques are more common in Chinese patients.

Methods: As part of the ongoing Culprit Plaque in Acute Cerebral Infarction study, patients with acute anterior circulation ischemic stroke were recruited at the University of Washington and the Beijing Tiantan Hospital. Plaque presence, location, and composition (intraplaque hemorrhage [IPH], lipid core, calcification, disrupted luminal surface [DLS]) in the carotid and intracranial arteries on the symptomatic side were evaluated using a 3D multi-contrast vessel wall MRI protocol. Carotid and intracranial arteries were reviewed independently by an experienced reader blinded to clinical characteristics and ethnic group.

Results: Twenty patients from the U.S. (median age: 59 years; 65% male) and 26 patients from China (58 years; 69% male) were evaluated. Of those, 18 U.S. patients (90%) and 20 Chinese patients (77%) had at least one plaque in either the carotid or intracranial arteries (p=0.4). Of those with plaque, 17 U.S. (94%) and 12 Chinese (60%) patients had carotid artery plaques (p= 0.02), and 11 U.S. (61%) and 19 Chinese (95%) patients had intracranial artery plaques (p=0.02). Features of possible culprit plaque (IPH and/or DLS) in the carotid artery were found in 8 U.S. patients (47%) but only 1 Chinese patient (8%) (p=0.04). Plaque composition in intracranial arteries was not significantly different between the two groups.

Conclusion: Possible culprit plaques in the carotid artery were more common in symptomatic U.S. patients than Chinese patients, while intracranial plaques were more common in the Chinese patients. Accurate localization of the culprit plaque has important implications for treatment.

Techniques and outcomes of emergency airway management in Japan: An analysis of two multicentre prospective observational studies, 2010-2016

OBJECTIVES

Continuous surveillance of emergency airway management practice is imperative in improving quality of care and patient safety. We aimed to investigate the changes in the practice of emergency airway management and the related outcomes in the emergency departments (EDs) in Japan.

METHODS

We conducted an analysis of the data from two prospective, observational, multicentre registries of emergency airway management-the Japanese Emergency Airway Network (JEAN)-1 and -2 Registries from April 2010 through May 2016.

RESULTS

We recorded 10,927 ED intubations (capture rate, 96%); 10,875 paediatric and adult patients were eligible for our analysis. The rate of rapid sequence intubation (RSI) use as the initial intubation method significantly increased from 28% in 2010 to 53% in 2016 (P_trend=0.03). Likewise, the rate of video laryngoscope (VL) use as the first intubation device increased significantly from 2% in 2010 to 40% in 2016 (P_trend<0.001), with a significant decrease in the rate of direct laryngoscope use from 97% in 2010 to 58% in 2016 (P_trend<0.001). Concurrent with these changes, the overall first-attempt success rate also increased from 68% in 2010 to 74% in 2016 (P_trend=0.02). By contrast, the rate of adverse events did not change significantly over time (P_trend=0.06).

CONCLUSION

By using data from two large, multicentre, prospective registries, we characterised the current emergency airway management practice, and identified their changes in Japan. The data demonstrated significant increases in the rate of RSI and VL use on the first attempt and the first-attempt success rate over the 6-year study period.

A comparison of emergency airway management between neuromuscular blockades alone and rapid sequence intubation: an analysis of multicenter prospective study

Background

Although airway management with neuromuscular blockade (NMB) alone is discouraged in the emergency department (ED), our previous study demonstrated that many patients were intubated using NMBs alone without sedatives. To refute this practice, we sought to compare the intubation success and adverse event rates between NMBs only and rapid sequence intubation (RSI).

Methods

This is a secondary analysis of the data from a prospective observational study of ED patients in 13 hospitals who underwent emergency airway management from April 2010 to August 2012. The primary outcome was intubation success rate on first attempt. The secondary outcomes were the intubation success rate in ≤2 attempts and the intubation-related adverse event rate. We compared these outcomes between intubation attempts using NMB alone and RSI. We fit multivariable logistic regression models adjusting for potential confounders (age, sex, weight, primary indication for intubation, and training level of intubators).

Results

Overall, 852 patients were eligible for this analysis, with 114 (13%) intubated with NMB alone and 738 (87%) with RSI. Between the NMB-alone and RSI groups, no significant differences were observed in the success rate on the first attempt (70 vs. 73%; P = 0.48) or in ≤2 attempts (89 vs. 91%; P = 0.46), or in the adverse event rate (11 vs. 12%; P = 0.58). Similarly, after adjusting for confounders, no significant differences were observed in any of these outcomes (all P > 0.05).

Conclusions

In this analysis of data from a large multicenter study of ED patients, we found no superior effectiveness of intubation with NMB alone when compared to RSI. Our data lend significant support to the concept that intubation with NMB alone should be avoided in the ED.

Nocturnal emergency department visits, duration of symptoms and risk of hospitalisation among adults with asthma exacerbations: a multicentre observational study

OBJECTIVES

We sought to compare the characteristics of patients with asthma presenting to the emergency department (ED) during the night-time with those of patients presenting at other times of the day, and to determine whether the time of ED presentation is associated with the risk of hospitalisation.

DESIGN AND SETTING

A multicentre chart review study of 23 EDs across Japan.

PARTICIPANTS

Patients aged 18-54 years with a history of physician-diagnosed asthma, presented to the ED between January 2009 and December 2011 OUTCOME MEASURES: The outcome of interest was hospitalisation, including admissions to an observation unit, inpatient unit and intensive care unit.

RESULTS

Among the 1354 patients (30.1% in the night-time group vs 69.9% in the other time group) included in this study, the median age was 34 years and ∼40% were male. Overall 145 patients (10.7%) were hospitalised. Patients in the night-time group were more likely to have a shorter duration of symptoms (≤3 hours) before ED presentation than those in the other time group (25.9% in night-time vs 13.4% in other times; p<0.001). In contrast, there were no significant differences in respiratory rate, initial peak expiratory flow or ED asthma treatment between the two groups (p>0.05). Similarly, the risk of hospitalisation did not differ between the two groups (11.3% in night-time vs 10.5% in other times; p=0.65). In a multivariable model adjusting for potential confounders, the risk of hospitalisation in the night-time group was not statistically different from the other time group (OR, 1.10; 95% CI 0.74 to 1.61; p=0.63).

CONCLUSIONS

This multicentre study in Japan demonstrated no significant difference in the risk of hospitalisations according to the time of ED presentation.

Multicentre observational study of adults with asthma exacerbations: who are the frequent users of the emergency department in Japan?

OBJECTIVES

Emergency department (ED) visits for asthma exacerbation reflect a failure of longitudinal asthma management. However, little is known about the characteristics of patients with frequent ED visits (≥2 visits in a 1-year period). We aimed to characterise the adult patients who frequently presented to the ED for asthma exacerbation in Japan.

DESIGN

A multicentre chart review study of 23 EDs across Japan.

PARTICIPANTS

Adults aged 18-54 years who presented to the ED with asthma exacerbation from 2009 to 2011.

OUTCOME MEASURES

Frequency of ED visits for asthma exacerbation in a 1-year period, including the index ED visit.

RESULTS

Of the 1002 eligible patients, 218 (22%) had frequent ED visits, accounting for 48% of total ED visits for asthma exacerbation in the 1-year period. Specifically, 12% had 2 ED visits and 10% had ≥3 visits. In these patients, guideline-recommended chronic management was suboptimal. For example, among patients with ≥3 ED visits, only 63% were treated with inhaled corticosteroids and 49% were current smokers. In a multinomial logistic regression model, markers of chronic asthma severity (history of hospitalisation for asthma and use of inhaled corticosteroids) were significantly associated with a higher frequency of ED visits (both p<0.05).

CONCLUSIONS

This multicentre study in Japan demonstrated that many patients are frequent ED users for asthma exacerbation. We also found that their asthma control management is suboptimal, most likely contributing to worse chronic severity and more frequent ED visits. Further dissemination and adoption of evidence-based guidelines are required to reduce asthma morbidity in this high-risk population.

Repeated attempts at tracheal intubation by a single intubator associated with decreased success rates in emergency departments: an analysis of a multicentre prospective observational study

OBJECTIVE

To determine whether the success rate of repeated attempts at tracheal intubation by a single intubator was lower than those by alternate intubators in the emergency department (ED).

METHODS

An analysis of data from a multicentre prospective registry (Japanese Emergency Airway Network Registry) of 13 academic and community EDs in Japan between April 2010 and August 2012. We included all adult and paediatric patients who underwent repeated attempts at tracheal intubation in the ED. We compared the intubation success rates at the second and third attempts between attempts at intubation by a single intubator who performed the previous attempts, and the attempts by alternate intubators.

RESULTS

We recorded 4094 patients (capture rate, 96%); 1289 patients with repeated attempts at tracheal intubation were eligible for this study. Among these, 871 patients (68%) had a second attempt at intubation by single intubators. At the second attempt, tracheal intubation by a single intubator was associated with a decreased success rate (adjusted odds ratio or AOR, 0.50; 95% CI 0.36 to 0.71), compared with alternate intubators. At the third attempt, intubation by a single intubator was also associated with a decreased success rate (58% vs 70%; unadjusted OR, 0.58; 95% CI 0.38 to 0.89). However, after adjustment for potential confounders, the association lost statistical significance (AOR, 0.89; 95% CI 0.52 to 1.56).

CONCLUSIONS

In this large multicentre study of ED patients undergoing tracheal intubation, second attempts at intubation by a single intubator, compared with those by alternate intubators, were independently associated with a decreased success rate.

Emergency airway management by resident physicians in Japan: an analysis of multicentre prospective observational study

Aim

To examine the success rates of emergency department airway management by resident physicians in Japan.

Methods

We conducted an analysis of a multicentre prospective registry (Japanese Emergency Airway Network Registry) of 13 academic and community emergency departments in Japan. We included all patients who underwent emergency intubation performed by postgraduate year 1 to 5 transitional or emergency medicine residents (resident physicians) between April 2010 and August 2012. Outcome measures were success rates by the first intubator, and by rescue intubator, according to the level of training.

Results

We recorded 4,094 intubations (capture rate, 96%); 2,800 attempts (2,800/4,094; 68%; 95% confidence interval (CI), 67%-70%) were initially performed by resident physicians. Overall success rate on the first attempt was 63% (1,767/2,789; 95%CI, 61%-64%); the rate improved over the first 3 years of training before reaching a plateau (P _trend < 0.001). Success rate by the first intubator was 78% (2,185/2,800; 95%CI, 76%-79%); the rate steadily improved as level of training increased (P _trend < 0.001). Of 597 failed intubation attempts by the first intubator, 41% (247/597; 95%CI, 37%-45%) of rescue attempts were performed by resident physicians. Success rate on the first rescue attempt was 76% (187/247; 95%CI, 70%-81%), and success rate by first rescue intubator was 89% (220/247; 95%CI, 85%-93%). These rates on rescue attempts steadily improved as level of training increased (both P _trend < 0.001). Intubations were ultimately successful in 2,778 encounters (99.6%).

Conclusion

In this multicentre study characterizing emergency airway management across Japan, we observed that emergency department intubations were primarily managed by resident physicians with acceptably high success rates overall.

Residency and career satisfaction among Anglo-American model emergency medicine residents in Japan

Aim

The number of institutions providing Anglo-American model emergency medicine has increased with the rise in its social demand in Japan. The ER Committee of the Japanese Association for Acute Medicine has introduced a residency model for use in Japanese hospitals that have adopted the Anglo-American emergency medicine model. Despite the critical importance of its quality, no studies have examined Japanese emergency medicine residents' level of satisfaction with their training. This study investigated their residency and career satisfaction, and factors associated with satisfaction.

Methods

We developed a cross-sectional, anonymous survey. Data were obtained from 67 Anglo-American model emergency medicine residents in Japan in February 2010. Data were analyzed with factor analysis and multivariable analysis with a logistic regression model.

Results

Response rate was 100% (n = 67). Overall, 50.7% and 67.2% of residents reported high residency and career satisfaction, respectively. Factor analysis derived four factors: working conditions; stress reduction; training systems; education. Logistic regression analysis revealed that the training system factor was significantly associated with high residency satisfaction (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.2-8.4) and the stress reduction factor was significantly associated with high career satisfaction (OR, 3.0; 95%CI, 1.2-8.4). A total of 28.8% reported intentions to switch specialties. The intention was not significantly associated with low residency satisfaction (OR, 1.7; 95%CI, 0.6-5.0), but was associated with low career satisfaction (OR, 5.1; 95%CI, 1.6-16.0).

Conclusion

Improvements in training systems and stress reduction may increase residency and career satisfaction of emergency medicine residents, respectively. This study suggested that high career satisfaction was required to secure future emergency physicians.